Interpretive Summary: Development of new techniques to improve and/or reduce the cost of using sex pheromones to manage codling moth remains an important objective in tree fruit pest management. Studies conducted by researchers at the USDA, ARS, Yakima Agricultural Research Laboratory, Wapato, WA have tested the effectiveness of dispensers loaded with either sex pheromone alone or in combination with pear ester for mating disruption of codling moth. Dispensers loaded with pear ester were shown to increase the proportion of unmated female moths in treated blocks. Meso dispensers applied at one tenth the number of dispensers as most standard pheromone dispensers were shown to be effective. Use of Meso dispensers should significantly reduce the application cost for growers without affecting the level of pest control.

Technical Abstract:
Studies utilized the attractive properties of pear ester, ethyl (E,Z)-2,4-decadienoate, and codlemone, (E,E)-8,10-dodecadien-1-ol, the sex pheromone of codling moth, Cydia pomonella (L)., for behavioural disruption. Standard dispensers loaded with codlemone alone or in combination with pear ester (combo) were applied at 500 – 1,000 ha-1. Larger (10-fold) combo dispensers (Meso) were evaluated at a rate of 80 ha-1. The addition of microencapsulated pear ester, PE-MEC, at 30 ml ha-1 was also evaluated. Male moth catches in unmated female-baited traps were lower in standard combo than in codlemone-treated blocks. Female moth catch in traps baited with pear ester, codlemone, and acetic acid in was significantly lower in standard combo than in codlemone-treated blocks. Male moth catch in unmated female-baited traps did not differ between combo and codlemone-treated blocks. However, mean catch was 50-60% lower in the combo-treated blocks. Fruit injury was significantly reduced with the addition of PE-MEC across untreated and dispenser treatments. Male moth catches were significantly lower in both the standard and Meso combo but not in the codlemone-treated blocks compared with the untreated control. The proportion of unmated females trapped was significantly higher in the standard combo than codlemone-treated and untreated blocks. The proportion of unmated females caught was higher in the Meso combo than in nearby or distant codlemone-treated blocks. The proportion of unmated females was significantly higher in all dispenser-treated blocks than in distant codlemone-treated blocks, but not different from the adjacent untreated blocks.